Double cam device for the control and selection of the needles of circular knitting machines and the like



FeB. 15, 1966 0 1 6 m n B 4 3 Kt 3 h E5 M5 D N A s E N I H C A M G G. AZZOLARI DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTIN Filed April 21, 1960 [NI/[N702 GU/DO A zzoLARi ATTORNE X5 G. AZZOLARI Feb. 15, 1966 3,234,760 DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES AND THE LIKE Filed April 21, 1960 5 Sheets-Sheet 2 E on a Z a a a aw n INVN70E Guipo AZZOLARI ATTORNE Y5 Feb. 15, 1966 G. AZZOLARI 3,234,760

DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES AND THE LIKE Filed April 21, 1960 5 Sheets-Sheet 3 gU/Do AzzoLnr-w mm a A TI'ORNE 75 Feb. 15, 1966 G. AZZ-OLARI 3,234,750

DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES AND THE LIKE Filed April 21, 1960 5 Sheets-Sheet 4 zwmrae Guipo AzzoLnRl ATTORNEYS Feb. 15, 1966 G. AZZOLARI 3,234,750

DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES AND THE LIKE Filed April 21, 1960 5 Sheets-Sheet 5 INVENTOR Guioo AzzoLnR/ ATTo RNELS United States Patent 3,234,760 DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES AND THE LIKE Guido Azzolari, Brignario dAdda, Italy, assignor to Fabrique Nationale dArrnes de Guerre, Societe Anonyme, Herstallez-Liege, Belgium Filed Apr. 21, 1960, Ser. No. 23,797 Claims priority, application Italy, Apr. 24, 1959, Patent 611,240; Apr. 15, 1960, Patent 682,450 Claims. (CI. 66-57) In some circular knitting machines for making hosiery, stockings and the like, it is necessary to be able to timely completely lift the knitting needles (specifically, those needles with long butts) into an operative position, and also bring them back to their inoperative position.

Usually these movements are produced by two profiled cams, which are brought into operative position then Withdrawn as the work proceeds. Each of these cams, in the present state of the art, form part of an independent control mechanism, the control mechanisms for the cams being actuated by the transmission of the machine.

It has also been proposed to combine the two cams with their independent control mechanisms, in such a way as to integrate them in a single body, while, however, providing for each earn an individual control means.

All such single body devices with totally separate mechanisms have substantial disadvantages resulting from a very complex construction and especially large overall dimensions. It is well known to those skilled in the art, that these large overall dimensions in the usual circular knitting machines produce serious difficulties in view of the need for conveniently arranging in an extremely small space, the relatively large number of mechanisms necessary for the normal operation of the machine. Also, the plurality of the control levers introduces, in the driving means therefor (the transmission of the machine), additional complications.

The invention relates to a device of the single body type and it is essentially characterised by the feature that the movements of the two cams are effected from a single control lever.

An advantage of the invention is the characteristic arrangement of an extremely simple, compact construction having small overall dimensions and supplying a mechanical combination which is relatively very simple.

With a view to explaining as clearly as possible the characteristic features of the invention, one embodiment of the invention, given by way of example, will now be described with reference to the accompanying drawings, in which:

FIGURE 1 is a perspective view of a circular knitting machine provided with the double cam device of the present invention;

FIGURE 2 is an enlarged perspective view of the head of the circular knitting machine shown in FIG. 1;

FIGURE 3 illustrates diagrammatically and in partial section a part of said head of the circular knitting machine;

FIGURE 4 is a front view of said double cam device, the two cams being shown in the inoperative position;

FIGURE 5 is a side View looking in the direction of the arrow F5, FIGURE 4;

FIGURE 6 is a section taken on line VI-VI of FIG- URE 4;

FIGURE 7 is a section taken on line VIIVII of FIG- URE 6, the upper cam being illustrated in the operative position and the lower cam being illustrated in the inoperative position;

FIGURE 8 is a section similar to that of FIGURE 7 ice but showing upper cam in the inoperative position and the lower cam in the operative position;

FIGURE 9 is a section taken on line IXIX of FIG- URE 8;

FIGURE 10 is a perspective view of the double cam device and a needle cylinder;

FIGURE 11 is a side view of a part of the needle cylinder and the raising cam in its operative position;

FIGURE 12 is a side view of a part of the needle cylinder and the lowering cam in its operative position.

Referring to FIGURES 1 to 3, the position of the double cam device according to the present invention, in a circular knitting machine, is indicated by A. The present double cam device is composed substantially of a single body 1, one of the major surfaces of which has two wide parallel transverse grooves 3, 4 connected together centrally by a passage 5. On this surface there may be applied a small plate 6 capable of being fixed on the said body 1 by screws 7, the correct position of the plate 6 being thus ensured by the lower shoulder 8 formed by the base 9 of the single body. At the place of the passage 5, the single body 1 has a cylindrical aperture 10 passing through it from side to side. In the upper groove 3 is fitted with a smooth frictional fit, the sliding cam carrier 11 having on its front, the upper cam 12 and on its rear, a heel 13, the latter containing an adjusting screw 14 movable to abut against the corresponding part of the single body 1. Starting from its lower edge the cam carrier 11 has a profiled notch 15. In the lower groove 4 is fitted with a smooth frictional fit, the sliding cam carrier 16 having on its front, the lower cam 17 and on its rear, a heel 18, the latter containing an adjusting screw 19 movable to abut against the corresponding part of the single body 1. Starting from its upper edge the cam carrier 16 has a profiled notch 20.

The cylindrical aperture contains a spindle 21 fitted with a smooth frictional fit, and retained on the one side by a bevel edged cylinder 22 and on the other side by a ring 23. At the place of the above mentioned passage 5, between the transverse grooves 3, 4, the spindle 21 is radially traversed by a pin forming on both sides of the spindle, two fingers 24, 25, the first being engaged in the notch 15 of the upper sliding cam carrier 11 and the second being engaged in the notch 20 of the lower sliding cam carrier 16. The finger 24 has a length slightly greater than that of the diametrically opposite finger 25, the arrangement being such that for the same angular displacement of the spindle 21 the corresponding linear displacement of the upper cam 12 is slightly greater than the corresponding linear displacement of the lower cam 17. The illustrated configuration of the notches 15 and 20 was found to provide excellent cooperation between the members 11, 16 and the radial fingers 24, 25. The pin forming the radial fingers 24, 25 is maintained in position by the intermediary of a locking screw 26. This screw 26 is engaged in a tapped aperture 27 provided in the corresponding part of the spindle 21 and of the head 22, the locking screw 26 being accessible through a tapped aperture 28 of larger diameter provided at the centre of the head 22 of the spindle 21. In this tapped aperture 28 is engaged the locking screw 29 providing for rigidly connecting the head 22 and the spindle 21 to the single operating lever 30 for the cams. The free end of this single lever may be pivoted at the end of a rod 31 joined at the other end to an operating mechanism, e.g. constituted by a rotating cam which, when operated, gives the rod 31 an upward or a downward axial displacement and maintains this rod in its extreme positions during predetermined time intervals. Hence, depending on this extreme position, a cam 12, 17 will then be maintained in its operative position during such a time interval. Each cam is permanently pressed into its operative position by an elastic means, In the embodiment shown in the drawings, the single body 1 has two blind apertures 32, 33 in which are located the corresponding parts of spiral springs 34, 35.

The portion of each of the springs which is directed towards the cams is located in a sleeve 36 or 37; each sleeve is fitted with a smooth frictional fit in the blind apertures 32, 33, and the closed end of each of these sleeves is applied on the rear surface of the respective cams 12, 17.

In this way the cams 12. 17 are permanently pressed towards their operative position by the springs and the cam which is to be moved into the inoperative position is pressed rearwardly by the operation in a suitable direction of the single lever which, on being displaced angularly, drives the spindle 21 and the lateral fingers 24, 25. Each finger is in permanent con-tact with the wall of the corresponding groove, but one of them presses the adjacent cam carrier rearwardly while compressing the return spring, whereas the other finger releases the corresponding cam carrier which, under the action of its return spring, brings the corresponding cam back into the operative position. The linear displacements of the cams 12, 17 towards their operative position may be adjusted and predetermined with great accuracy by the abutment screws 14, 19. The rear or inoperative position is determined by the length of the fingers 24, 25 in co-operation with the corresponding notches 15, 20 of the sliding cam carriers 11, 16.

It will be noted that the withdrawal of a cam into the inoperative position causes compression of its return spring so that its return into the operative position can be effected later at very great speed.

The double cam device cooperates with the needles of the needle cylinder 38 which is rotated.

The needle cylinder 38 is concentrically mounted inside the casing 39. The hollow axle 40, forming a cylinder carrier, is adapted to be driven in rotation by a bevel gear 41, the driving ring gear 42, the coaxial bevel gear 43, the bevel gear 44 and driving means (not shown).

Referring to FIGURES 10, 11 and 12, the cooperation of the double cam device with the needles of the needle cylinder 38 is as follows:

Normally a needle cylinder of this type is provided over a part of its periphery with needles having a long butt and over another part of its periphery with needles having a short butt. The length of these short butts is such that they cannot be engaged by the above cams 12 and 17 when the cylinder is rotating in front of these cams. Needles 45 with a long butt 46, on the contrary, are adapted to be engaged by these cams.

Supposing that the raising cam 17 is in its operative position, whereas the lowering cam 12 is withdrawn, the butts 46 of the needles 45 will ride up the upper part 47 of the raising cam 17 when the needle cylinder is rotating. In this manner these needles are brought in their raised position, whereas the needles with short butts remain in their lower position. Hence only a part of the needles, namely, those with the short butts, will be used in the knitting operation. This is necessary when, for instance, the heel of a stocking must be knitted.

When the raised needles are to be brought back to their lower position, i.e. when the knitting operation of the heel or the tip is finished, the raising cam 17 is withdrawn, while the lowering cam is brought in its operative position. From the drawings it is clear that, in this case, the butts of the raised needles will ride down the lower surface of the lowering cam 12 so that these needles are brought in their lower position.

It is obvious that the invention is not limited to the precise construction described and that the different parts described and illustrated can be replaced by any other equivalent parts or operating devices.

What I claim is:

I 1. A double cam device for the control and selection of the needles of circular knitting machines, comprising a single body, two sliding cam carriers in said body each mounting a cam, elastic means pressing each of these cams into an operative position, means moving when required either one of said cams into an inoperative position, and a single operating member for the last-mentioned means, wherein the single body has two blind apertures, said device further comprising a pin located in each aperture with a smooth frictional fit, the end of each pin being outwardly directed, and a spiral spring bearing on one side on the end of each blind aperture and on the other side on the end of each corresponding pin, said ends being permanently pressed against the rear surface of the corresponding cam.

2. Device according to claim 1, wherein said single body is of prismatic shape, one major surface having two parallel transverse grooves joined centrally by a passage the bottom of which has a cylindrical aperture passing through said body from side to side thereof, said device further comprising a small plate fixed on the said major surface, said plate being also traversed by a cylindrical aperture which is co-axial with the above mentioned cylindrical aperture passing through the single body.

3. Device according to claim 2, characterized by the feature that in each of the two transverse grooves of the single body there is fitted with a smooth frictional fit a sliding cam carrier terminating on one side in a cam and on the other side by a heel traversed by an adjusting screw, each cam carrier having on its inwardly directed edge a notch such that when the two cams are in position the said notches face each other and are disposed in line with the passage joining the two transverse grooves of the single body.

4. Device according to claim 2, comprising a spindle a cylindrical head having a beveled edge, a ring, said spindle being retained on one side by said head and on the other side by said ring, and a pin forming two fingers of diflerent lengths and diametrically traversing said spindle, said spindle traversing the cylindrical apertures of the single body and of its closure plate.

5. Device according to claim 4, comprising two pressure screws, the pin passing diametrically through the operating spindle of the cams and forming the operating fingers thereof being maintained in position by one of said pressure screws which is engaged in an axial tapped aperture disposed in the extension of a tapped aperture of larger diameter in the head of the spindle, the other pressure screw being engaged in the last-mentioned aperture and adapted to rigidly connect the spindle to a single operating lever for the two cams.

References Cited by the Examiner UNITED STATES PATENTS 1,841,205 1/1932 Page et a1 66-48 2,178,911 11/1939 Lawson 66-43 2,756,575 7/1956 Haddad 6643 3,046,763 1/1962 Lawson 6643 DONALD W. PARKER, Primary Examiner.

LEYLAND M. MARTIN, RUSSELL C. MADER,

Examiners. 

1. A DOUBLE CAM DEVICE FOR THE CONTROL AND SELECTION OF THE NEEDLES OF CIRCULAR KNITTING MACHINES, COMPRISING A SINGLE BODY, TWO SLIDING CAM CARRIES IN SAID BODY EACH MOUNTING A CAM, ELASTIC MEANS PRESSING EACH OF THESE CAMS INTO AN OPERATIVE POSITION, MEANSA MOVING WHEN REQUIRED EITHER ONE OF SAID CAMSA INTO AN INOPERATIVE POSITION, AND A SINGLE OPERATING MEMBER FOR THE LAST-MENTIONED MEANS, WHEREIN THE SINGLE BODY HAS TWO BLIND APERTURES, SAID DEVICE FURTHER COMPRISING A PIN LOCATED IN EACH APERTURE WITH A SMOOTH FRICTIONAL FIT, THE END OF EACH PIN BEING OUTWARDLY DIRECTED, AND A SPIRAL SPRING BEARING ON ONE SIDE ON THE END OF EACH BLIND APERTURE AND ON THE OTHER SIDE ON THE END OF EACH CORRESPONDING PIN, SAID ENDS BEING PERMANENTLY PRESSED AGAINST THE REAR SURFACE OF THE CORRESPONDING CAM. 